A DRAM capacitor is taken as an example of a semiconductor device provided with a thin film such as an electroconductive metal film.
Research has been actively carried out to metallize a lower electrode film or an upper electrode film in order to assure accumulated charge capacity in the DRAM capacitor, with a fine pattern of the DRAM capacitor. For example, noble metals Ru, Pt, Ir or oxides thereof are candidates for the material of the lower electrode film or the upper electrode film. Also, TiN, TaN, and the like are used as the material of the barrier metal film.
A cylinder shape having a high aspect ratio is mainly used as the shape of a capacitor electrode. For this reason, all films including the lower electrode film, the upper electrode film, and the barrier film require excellent step coverage.
In view of the above situation, not a conventional sputtering method but a CVD method, which has excellent step coverage, has been used as a film formation method. Particularly reaction between an organic metallic liquid source, and oxygen containing gas, hydrogen containing gas or nitrogen containing gas is used.